1. Field of the Invention
The present invention relates to an exhaust treatment unit for treating exhaust gas from an engine of a work vehicle.
2. Background Information
Work vehicles such as a hydraulic excavator are equipped with an exhaust treatment device. The exhaust treatment device is connected to an engine through a connection pipe (note the connection pipe connected to the engine is hereinafter referred to as a first connection pipe) in order to treat the exhaust gas from the engine. As described in Japan Laid-open Patent Application Publication No. JP-2012-097413(A), for instance, the exhaust treatment device includes a diesel particulate filter device and a selective catalytic reduction device (SRC catalytic converter).
The diesel particulate filter device is connected to the first connection pipe and performs treatment of reducing particulates contained in the exhaust gas from the engine. The exhaust gas after the treatment is transferred to the selective catalytic reduction device through a connection pipe (note the connection pipe connecting the diesel particulate filter device and the selective catalytic reduction device is hereinafter referred to as a second connection pipe). The selective catalytic reduction device reduces nitrogen oxide (NOx) contained in the exhaust gas treated by the diesel particulate filter device. In some cases, these two exhaust treatment devices and the second connection pipe are installed in a work vehicle as a single unit for implementing easiness of maintenance. Such unit is referred to as an exhaust treatment unit.